Globalization and international trade have led to increased emissions as factories have moved to developing countries with less strict environmental regulations. China in particular exports over a third of its goods and has become the world's largest carbon emitter due to its coal-dominated energy system and large trade surplus. While China's exports consist mainly of less carbon-intensive goods like textiles rather than steel, countries importing from China are effectively outsourcing their emissions. One proposed solution is a border tax adjustment for imports into regions with emissions caps to make costs more evenly distributed.